Taking to his Instagram account, Armstrong posted a picture of K-pop star Psy, and what he had to say about the “Gangnam Style” hit-maker was far from congratulatory.

“This dude is the herpes of music,” Armstong wrote. “Once you think it’s gone, it comes back.” The Green Day singer also added a series of hashtags: #herpes, #flarup and #pleasegoaway.

Posted on Tuesday (May 7), by the following day the missive has generated more than 20,000 “likes” from Instagram users, with nearly 2000 comments from fans mostly agreeing with Armstrong’s commentary.